Recreation vehicles, such as campers, trailers, motor vans, motor coaches, small boats, and the like, are commonly provided with ventilation devices to provide for interior ventilation both during vehicle motion and when the vehicle is at rest. Such ventilation openings may be seen by way of example in U.S. Pat. Nos. 3,587,443 and 4,038,911, assigned to the assignee of the present invention, the disclosures of which are hereby incorporated by reference.
Such ventilators typically include a ventilation opening mounting which is affixed in some way to the vehicle in question to cover a hole formed in the vehicle of like size and shape to the ventilation opening mounting. The ventilation opening mounting in turn has attached to it a pivoted cover and an operating mechanism for operating the cover to position the cover in any of the plurality of selected positions between fully opened and fully closed. The ventilation mounting also has attached to it a screen which serves the purpose of preventing the entry of unwanted insects and the like into the vehicle through the ventilation opening when the cover is in any of its open positions. In U.S. Pat. No. 3,587,443, a screen adapter is connected to the ventilation opening mounting by screws, and in addition, a screen frame is snap-locked into the screen adapter by a pair of latch members which contain pawls at the end thereof, each of which engages a respective lip formed to extend outwardly from the side wall of the screen adapter. The apparatus shown in U.S. Pat. No. 4,038,911 attaches a screen frame to the ventilation opening mounting by screwing the screen frame into a support bar which extends across the ventilation opening.
These ventilation openings and their associated screens are generally not high priced items, and any saving in the construction and/or assembly time of such apparatus can markedly improve the percentage of profit available from the sale of such items. While the apparatus shown in the U.S. Pat. No. 4,083,911 is certainly very rugged and durable, the manufacturing time necessary for fitting the pieces together and screwing in the necessary screws to attach the screen to the entire assembly is a labor intensive portion of the manufacturing process, which is desirably cut down or eliminated entirely. With respect to the apparatus of U.S. Pat. No. 3,587,443, there also exists the necessity for screwing in order to attach the screen adapter in order to thereafter attach the screen.
It has also been found, that the snap locking arrangement for the apparatus shown in that patent is not entirely satisfactory. The pawl and lip arrangement is not as strong as is desirable, especially if the vehicle owner removes the screen frame for cleaning the screen. After several such cycles, the arm containing the snap lock tends to become weakened or permanently deformed causing the latch members to improperly engage the engaging lips, resulting in the screen tending to become dislodged from the vent or to rattle excessively.
The above-noted deficiencies of and problems with the prior art are not intended to be exhaustive, but rather are intended to illustrate that the existing vehicle vents in the art are not entirely satisfactory.
Recognizing the need for an improved vehicle vent, and particularly, an improved means for securing the screen frame in place in a vehicle vent, it is the general object of the present invention to provide an improved vehicle ventilation opening and means for attaching the screen frame to the ventilation opening.
A feature of the present invention resides in providing a support bar connecting opposite walls of the ventilation opening in which are positioned pawl openings for receiving pawls on the ends of pawl arms mounted to the screen frame with the pawl arms being equipped with a spine on the surface of the pawl arm opposite from that containing the pawl. The spine serves a dual function of bracing the flexible pawl arm during insertion of the pawl into the pawl opening, and blocking deflection of the pawl arm, once the pawl has passed through the pawl opening, which deflection would be sufficient to disengage the pawl from the pawl opening.
A further feature of the present invention in one embodiment thereof resides in forming the ventilation opening, including the support, from plastic and providing in the pawl opening a flexible pawl opening tongue which has a spine performing a bracing function like that of the pawl arm spine.
Still another feature of the present invention is a sloping surface on the pawl arm spine at the terminal end thereof, which facilitates entry of the pawl arm and the pawl arm spine into the the pawl arm opening as the pawl arm is deflecting sufficiently to allow the pawl to clear the pawl opening. The pawl arm is deflected prior to the pawl snapping into a mated position with the pawl extending above the surface of the support bar adjacent the pawl opening.
A still further feature of the present invention is the provision of a ramped surface on the pawl opening tongue to facilitate both deflection of the pawl opening tongue and movement of the pawl into the pawl opening during the insertion of the pawl into the pawl opening.
Still another further feature of the present invention is the provision of shoulder members on either side of the pawl arm having abutting surfaces which abut the support bar when the pawl is in the mated position.